JD4520 Blue Smoke

[Hay maker2]

I have a JD4520 that I have started to work on, this is a true 4520 without the updates.

When the tractor starts and idles there is a nice cloud of white / blue smoke from the exhaust. Under a little load or more, the smokes clear up. It starts with no hesitation. New air filters. Precleaned removed & cleaned, no obstructions. I put it on my dyno and Im getting 120HP. If I start working it on the dyno it gets a little black smoke around 130HP. To me everything seems fine. If the compression was low, I do not think it would start this easy. Maybe there is an oil leak in the turbo causing the smoke? Any thoughts?
Thanks

 

[tomstractorsandtoys]

If it has the small injection pump most of them do smoke blue at idle. The little pumps do seem to put out a little more power than the big
ones. For all the aggravation those little pumps have caused I wonder how much money Deere saved by using them when the tractors were new?
Maybe the small pumps were not Deere's idea and were what Rosa Master supplied? I think all 4520's had them and on other tractors it was just
some. There were a few used on 2510's,1020 and 2020 tractors and maybe 1/3 of the side console tractors had them. Tom

 

[ss55]

Are you sure the light black smoke at 130 HP is not just excess fuel that was not burned? An oil leak at the turbo would cause smoke at all power levels, maybe even increasing at lower power levels.

 

[coonie minnie]

Tom, I could be completely wrong on this, but I thought all the '69 and '70 4020s used the small pump? We have a '69 here that came new with the small pump, but it was converted to the older style, big pump rather quickly.

 

[Hay maker2]

(quoted from post at 13:48:42 06/05/22) If it has the small injection pump most of them do smoke blue at idle. The little pumps do seem to put out a little more power than the big
ones.
Maybe the small pumps were not Deere's idea and were what Rosa Master supplied? I think all 4520's had them and on other tractors it was just


It has the JDB pump.
I assume this is the small pump?

 

[Dieseltech]

J D had Stanadyne/RoosaMaster build the C series pump for
Deere only because Deere got tired of customers
commenting, your tractors have the same make injection
pump the competition uses. SO, the piece of crap C pump
came to life. While some do perform well, most didnt, and will
NEVER approach the fuel delivery the DB/JDB is capable of.
Actually, the shoes/rollers and leaf spring are the same in
BOTH pumps. The C pumps downfall is the lousy governor
action. My 1970 4020 Powershift still has the C pump, and it
WILL be replaced soon with a JDB thats ready to put on.

 

[tomstractorsandtoys]

I am not sure if it was a serial number or production year when they were new. Many have been changed. I have a late 3020 diesel engine that we plan to change sometime. Tom

 

[8850dave]

I thought the real late 4520 tractors had the tall pump from the factory.